uxTaskGetSystemState() callable from an ISR

Kernel
1

Hello,
I have added a call to uxTaskGetSystemState() within an ISR on an ARM M4. Is this recommended/safe?
Many Thanks,
Vince

2

It’s not since it calls pvPortMalloc and sprintf internally which are usually not possible in ISRs. See the source of this function in FreeRTOS-Kernel/tasks.c at main · FreeRTOS/FreeRTOS-Kernel · GitHub.
Also note the basic rule that only FreeRTOS API calls with the FromISR suffix can be used in ISRs.

3

Many Thanks for the response Hartmut!

4

It is also quite a lengthy function, which, depending on the rest of your system, can be an issue for an ISR.